Global genomic U.S. Pat. No. 4,448,150 describes a system that uses side-mounted lights for monitoring animals. U.S. Pat. No. 5,608,209 relates to quantification of specific animal behaviors and describes a system using optical emitters in conjunction with optical sensors to measure behaviors within the cage. U.S. Pat. No. 5,685,637 discloses an illumination device that uses a single broad-spectrum light bulb in combination with a ring of infrared light-emitting diodes (LEDs). U.S. Pat. No. 6,953,266 describes a system for illuminating animal cages in a rack. The system uses LEDs and fiber optic cables to light the cages from the side. U.S. Pat. Nos. 5,915,332 and 7,086,350 are for systems designed to monitor and measure animal behaviors. They both focus on methods and systems to monitor specific behaviors using indicators for these behaviors.